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Acids and alkalis are of great importance as industrial chemicals. When ranked by volume of production, the inorganic acids and alkalis (including chlorine and ammonia) are 5 of the 10 major chemicals produced yearly in the United States.
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ESSENTIALS OF DIAGNOSIS
Acute effects
Irritative dermatitis, skin burn.
Respiratory irritation, pulmonary edema.
Chronic effects
Hydrofluoric acid: osteosclerosis.
Nitric acid (oxides of nitrogen): bronchiolitis fibrosa obliterans.
Chromic acid: nasal ulceration, perforation, skin ulceration.
Sulfuric acid: laryngeal cancer.
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General Considerations
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An inorganic acid is a compound of hydrogen and one or more other elements (with the exception of carbon) that dissociates to produce hydrogen ions when dissolved in water or other solvents. The resulting solution has the ability to neutralize bases and turn litmus paper red. Inorganic acids of greatest industrial use are chromic, hydrochloric, hydrofluoric, nitric, phosphoric, and sulfuric acids. Inorganic acids share certain fire, explosive, and health hazards.
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Organic acids and their derivatives include a broad range of substances used in nearly every type of chemical manufacture. All have primary irritant effects depending on the degree of acid dissociation and water solubility.
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Use, Production, & Occupational Exposure
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Sulfuric acid is the leading chemical in production volume. It is less costly than any other acid, can be handled easily, reacts with many organic compounds to produce useful products, and forms a slightly soluble salt with calcium oxide or calcium hydroxide. The majority of sulfuric acid is used in the manufacture of phosphate and other fertilizers, petroleum refining, production of ammonium sulfate, iron and steel pickling, manufacture of explosives and other nitrates, synthetic fiber manufacture, and as a chemical intermediate. Workers with potential exposure to sulfuric acid include electroplaters, jewelers, metal cleaners, picklers, and storage-battery makers. Occupational exposure can occur both by skin contact and by inhalation of sulfuric acid mist.
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Phosphoric acid is used predominantly in the manufacture of fertilizers and agricultural feeds, in water treatment, and as a component of detergents and cleansers. Other uses include the acid treatment (pickling) of sheet metal, chemical polishing of metals, as a tart flavoring agent for carbonated beverages, as a refractory bonding agent, and for boiler cleaning, textile dying, lithographic engraving, and rubber latex coagulation. Occupational exposure occurs primarily to the liquid acid by skin contact.
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Chromic acid is produced by roasting chromite ore with soda ash and treatment with sulfuric acid to form chromic acid anhydride, chromic acid (chromium trioxide), and dichromic acid. Chromic acid is used in chromium plating, process engraving, cement manufacturing, anodizing, metal cleaning, tanning, and the manufacture of ceramic glazes, colored ...